The latest drug-pricing drama has pushed the debate in a new direction. It would be a mistake for biotech shareholders to dismiss the uproar as the same old story.

Marathon Pharmaceuticals’ decision to list the old steroid deflazacort at an $89,000 annual price to treat Duchenne muscular dystrophy, and the resulting outcry, has had an immediate impact on the company. Marathon said Monday that it plans to delay the drug’s U.S. launch, scheduled for next month, after politicians in Washington expressed anger over the company’s...